As I was adding to the library, reading some of the essays as I linked to them, I came across an essay written by Daniel Dennett in 1988 called "Quining Qualia. The essay, which is amazingly well-written, attempts to eliminate the "special" treatment of qualia in our language and in scientific investigation of our sensations.

Qualia have been notoriously difficult to define linguistically, namely because they rely on intuitions other than what we can express with language. (s.q. How do we talk about the experience of the color red without using the term red?)

However, Dennett aims to show that qualia do not have any special significance, and that the introduction of qualia to the sciences renders it useless.

In brief, Dennett proposes the following:

He states qualia is supposed to represent the ultra-intuitive way things seem to us.

He defines to quine as "to deny resolutely the existence or importance of something real or significant." (Obviously a joke on W.V. Quine's rejection of the analytic/synthetic distinction.)

He asserts that "conscious experience has no properties that are special in any of the ways qualia have been supposed to be special," and later, that the theoretical foundation for believing qualia to be of extra explanatory value is fundamentally flawed.

He reinforces the criticism that qualia are supposed to be intuitive, and that if we can simply redefine qualia to satisfy something already well-understood, then qualia is just an excess term to our vocabulary without any special significance of its own. In other words, if we can associate the term qualia with some referents to which we already provide a name, then qualia doesn't stand to very worthwhile evaluation.

In defense of (3.), he invokes fifteen "intuition pumps" (a.k.a. "though experiments") that are supposed to lead us away from the misleading belief in qualia.

Pump 1: Watching you Eat Cauliflower. Say someone who hates cauliflower watches someone eat cauliflower, which leads the person to wonder how someone could possibly enjoy the taste. We may hypothesize that cauliflower tastes different to them, which seems plausible. Surely things taste different to me once I have mixed them with other things, or had I a different palette. However, if these processes are subjective in nature, how could we possibly narrow them down to some fundamental properties about which we could make serious discussion? I could categorize every "qualia," then, into the times and subjectivities of the qualia experienced, but that gets us no closer to understanding some fundamental property of cualiflower or maple syrup. As Dennett writes, "The homely cases convince us of the reality of these special properties--those subjective tastes, looks, aromas, sounds--that we then apparently isolate for definition by this philosophical distillation."

Pump 2: The Wine-Tasting Machine. This reminds me a lot of Searle's Chinese Box Argument and Jackson's Mary's Room Argument. It is feasible for us to create a machine that, associating what professional wine tasters find pleasing in wine to the chemical makeup of wine, judges the taste of the wine for us. However, no qualia believer would assent that our experience of tasting wine is anything remotely similar to the way a robot tastes wine. The arguments defending this, though, are not very good, relying on a sense that qualia in are "ineffable", "intrinsic," "private," and "directly or immediately comprehensible to consciousness." But if this is so, how can we be certain that robots do not experience them? Or worse yet, how do we even talk about such a thing objectively? He then takes an appeal to Wittgenstein's Philosophical Investigations. I'll give (#293 - #298) to fill context.

#294. If I say to myself that it is only from my own case that I know what the word "pain" means--must I not say the same of other people, too? And how can I generalize the one case so irresponsibly?

Now someone tells me that he knows pain is only from his own case!--Suppose everyone had a box with something in it: we call it a ‘beetle’. No one can look into anyone else's box, and everyone says he knows what a beetle is only by looking at his beetle. — Here it would be quite possible for everyone to have something different in his box. One might even imagine such a thing constantly changing. — But suppose the word ‘beetle’ had a use in these people's language? — If so it would not be used as the name of a thing. The thing in the box has no place in the language game at all; not even as a something: for the box might even be empty. No, one can ‘divide through’ by the thing in the box; it cancels out, whatever it is.

That is to say: if we can construe the grammar of the expression of sensation or the model of 'object and designation' the object drops out of consideration as irrelevant.

#295."I know....only from my own case"--what kind of proposition is this meant to be at all? An experiential one? No.--A grammatical one?

Suppose everyone does say about himself that he knows what pain is only from his own pain.--Not that people really say that, or are even prepared to say it. But if everybody said it--it might be a kind of exclamation. And even if it gives no information, still it is a picture, and why should we not want to call up such a picture? Imagine an allegorical painting taking the place of those words.

When we look into ourselves as we do philosophy, we often get to see just such a picture. A full-blown pictorial representation of our grammar. Not facts; but as it were illustrated turns of speech.

#296. "Yes, but there is something there all the same accompanying my cry of pain. And it is on account of that that I utter it. And this something is what is important--and frightful."--Only whom are we informing of this? And on what occasion?

#297. Of course, if water boils in a pot, steam comes out of the pot and also pictured steam comes out of the pictured pot. But what if one insisted on saying that there must be something boiling in the picture of the pot?

#298. The very fact that we should so much like to say: "This is the important thing"--while we point privately to the sensation--is enough to shew how much we are inclined to say something which gives no information.

Pump 3: The Inverted Spectrum. A famous argument, it asserts that our learning a common language of associating experiences of properties to things does not imply that we experience the same thing. People who see green instead of red may use the same word to refer to it, but this confuses this objective qualia that we are supposed to intuit.

Pump 4: The Brainstorm Machine. Supposing we had some sort of machine that could fit on my head and report someone's inverted spectrum experience, I would report the findings invertedly. But then say the technician inverts the plug such that the socket reads as I am used to reporting my experiences (matching his experiences to mine, if you will). How would we determine which orientation was the correct one?

Pump 5 and 6: The Neurosurgical Prank and Alternative Neurosurgery. Assuming that we awaken with an inverted spectrum, we seem perfectly capable of explaining the changes in our perception and even place blame, but this runs into a problem of finding which operation the neurophysiologist actually performed. Did he change all of my memories of past qualia, or was my qualia switched at the ocular nerve? Both stories are plausible explanations for a perceptive switch, but we couldn't then pinpoint what the "original" qualia were with any accuracy, and so the issue remains.

Pump 7: Chase and Sanborn. Two Maxwell House tasters, Chase and Sanborn, agree in their acquired distaste for Maxwell House coffee. However, Chase bases his distaste for coffee on a change in his tastes, while Sanborn claims that his distaste comes from some change of his tasters. Who are we to believe? Is there any more value to claiming that the taste has remained constant, but that the cause of their distaste is his experience with better coffees, or that the cause of their distastes is caused by some modification in their anatomy, making them taste the original coffee differently?

Pump 8: Gradual Post-Operative Recovery. Expanding on the prior "pump," if we actually performed a surgery that altered Chase's experience of certain tastes, but that his behavior gradually showed a recuperation of those original tastes, what do we say about his memory? Is there an alteration in how he compares his memories, or in how he accesses them? Either would feasibly explain a drift into a regaining of the "same state" of taste, even if the surgery has not been reversed. Not only can the subject of the surgery not reasonably assert one difference over another, neither can a third-person observer, since he can only go by the behavior and contribution of the subject. Now, the qualia have evaded both the testee as much as the tester.

Pump 9: The Experienced Beer Drinker. No one likes the taste of beer on the first sip, but come to like it over time. But then the qualia of the beer, if they are said to change with further drinking, actually changes with the quantity consumed. This challenges beer's qualia (its taste) as being an "intrinsic" property (a property of the beer independent of relation), but poses it instead is an "extrinsic" property (that requires relation to the quantity of beer drunk). However, if this can be generalized to all cases, then there are no intrinsic properties to which qualia (as a term) can provide any insight.

Pump 10: Worldwide Eugenics. A chemical x exists which tastes bitter to 75% of the human population, and so a popular belief of the qualia of this chemical x could be altered by simply performing a vast eugenics project on those who perceive chemical x as bitter. If we do that, though, then collective opinion appears to dictate what we take as "qualia" for chemicals, and our notion of qualia has nothing to do with some intrinsic property of the chemical, itself.

Pump 11 and 12: Cauliflower Cures and Visual Field Inversion Created by Wearing Inverting Spectacles. Recalling Pump 1, Dennett professes to hate cauliflower. But someone may offer Dennett a pill that promises "that after [he] swallows this pill cauliflower will taste exactly the same to [him] as it always has, but [he] will like that taste!" It is possible to do (say the taste of cauliflower triggers parasympathetic responses akin to a eating chocolate cake, though it definitely still tastes like cauliflower). It sounds like we may have retained intrinsic properties like the qualia we have defined. However, any talk of this involves an imagination and philosophical jargon-ing of the very qualia that we aim to characterize, and so begs the question.

Pump 13: The Osprey Cry. This is an analog of Wittgenstein's Private Language Argument, instead dealing with distinguishing bird calls rather than noting intrinsic feelings.

Pump 14: The Jello Box. In the days of spies, two people who needed to be careful about identifying each other would carry a half of a ripped Jello box, making a forged match incredibly difficult. And we may find an analogy to this with our ostensive (or even more complex forms of) reference. My friend and I may experience the world very differently, which is not contested. Dennett appears to propose that attempting to refer to intrinsic properties is really an effort to narrow down "idiosyncrasies" that some speakers carry along with the uses of terms, idiosyncrasies we could detect without an utterance of qualia.

Pump 15: The Guitar String. Upon plucking a guitar string, we are able to alter the same note in a few ways. If may strike an E string open in two different ways, but we may describe a second as "bottoming out" after we heard the first. But if one the first, we called that note a distinct sound, then we were really mis-ascribing a complex experience with a single term, which could be divided into other terms to refer to the two portions of the same note working together. It would be a mistake, one may imply, to believe that there is something atomic about our use of reference as the distinguishing mark for qualia, but then it leaves us without a valuable explanation of what else we have. Qualia depends on a sense of some sort of references to the atomic quale of all experiences, but trying to gather them from experience itself doesn't help, since our capacity for reference and isolation of referents is conceivable infinite.

Dennett summarizes:

So when we look one last time at our original characterization of qualia, as ineffable, intrinsic, private, directly apprehensible properties of experience, we find that there is nothing to fill the bill. In their place are relatively or practically ineffable public properties we can refer to indirectly via reference to our private property-detectors-- private only in the sense of idiosyncratic. And insofar as we wish to cling to our subjective authority about the occurrence within us of states of certain types or with certain properties, we can have some authority--not infallibility or incorrigibility, but something better than sheer guessing--but only if we restrict ourselves to relational, extrinsic properties like the power of certain internal states of ours to provoke acts of apparent re-identification. So contrary to what seems obvious at first blush, there simply are no qualia at all."

A starter question: Is this really an act of quining, or is there not any reasonable value to claiming the existence qualia at all?